This invention relates to rotatable seals having an outer housing body and an inner rotor wherein the body and rotor have aligned bores for locking a cable to the seal by relative rotation of the rotor to the body.
U.S. Pat. No. 5,180,200 (""200) discloses a rotatable seal having an arrangement for axially locking the rotor to the housing bore and for rotationally locking the rotor after it is rotated to secure a wire to the rotor. The wire is inserted in the device bores and the rotor is axially secured in a first position where the wire is wrapped about the rotor. The rotor is then axially displace to a second position where engaged teeth rotatably lock the rotor to the housing. A tool may be required to displace the rotor to the second axial position. The wire is inserted in a direction normal to the rotor rotation axis.
U.S. Pat. No. 5,419,599 (""599) discloses a rotor that is also locked axially to the housing bore in two positions. However, the rotor has wire receiving slots rather than circular bores so that the rotor can be axially displaced to a second axial position with the wire inserted in the rotor. Ratchet teeth and pawls permit the rotor to be relatively rotated to the housing in one direction after the rotor is fully axially inserted in the housing bore with the wire in place. No tools are required to insert the rotor to the second position as in the above described seal.
U.S. Pat. No. 6,000,736 (""736) discloses a rotatable seal with a slot in the housing outer bores so the bores communicate. This permits the wire to be partially wrapped about the rotor to secure one wire end to the rotor. The other end can later be inserted into the housing and into a second bore in the rotor without being blocked by the partially wrapped wire. The rotor and housing include a ratchet and pawl mechanism for locking the rotor rotational in one direction relative to the housing.
U.S. Pat. No. 6,007,121 discloses a rotatable seal wherein unlike the seals in the above patents, the wire to be secured is inserted in a direction parallel to the rotor rotation axis rather than normal to that axis. In this structure the wire is twisted about itself or a post in the housing chamber about the rotational axis. Further, the rotor has a weakening groove adjacent to an outer surface of the rotor such that the central portion of the rotor will fracture if the wire is pulled with excessive force in a withdrawal direction along the rotor axis. Fracturing the rotor makes it unusable and provides tampering evidence.
In the seals of the of the xe2x80x2200, xe2x80x2599 and xe2x80x2736 patents, the wires are all inserted in a direction normal to the rotor axis. As the rotor is rotated the wires wrap about the rotor. Where one wire is inserted first to be locked to the rotor and then later an end user inserts the free end into the remaining seal bore to lock the free end to the rotor, a problem arises whereas the first wire end when wrapped may block the rotor bores preventing or resisting insertion of the free end into a rotor bore. At times, the rotor may be wound several times causing several wraps of wire about the rotor. This may completely block the remaining rotor bore preventing the free end from being engaged with the rotor and being locked.
The present inventors recognize a need to optimize the seal structure so that it is easily used at all times by a user.
A security seal according to one aspect of the present invention that solves the above problems comprises a filament and a housing defining a chamber having an axis, at least one opening is through the housing in communication with the chamber, first and second portions of the filament being received in the at least one opening normal to the axis and for securing the seal to an article. A rotor is in the chamber and has at least one bore and is rotatable about the axis, the at least one bore being aligned with the at least one opening, the rotor and housing chamber forming a filament receiving chamber, third and fourth portions of the filament being received in the at least one bore, the rotor including a rib for forming the filament receiving chamber into at least one sub-chamber, the rib for guiding the received filament into the at least one sub-chamber. One way motion means permit the rotor to be relatively rotated with respect to the housing in only one direction about the axis for wrapping the received filament about the rotor in the at least one sub-chamber to secure the received filament to the rotor and housing.
In a further aspect, the at least one bore and at least one opening lie in a plane, the plane defining upper and a lower rotor sections, the rib being located in the plane.
In a further aspect, the rotor at least one bore lies in a plane defining rotor upper and lower sections, the housing and rotor including complementary locking means for axially locking the lower section to the housing in the chamber, the rib being located in the plane.
The rib preferably comprises a V-shaped member but may have an external surface that is arcuate.
In a further aspect, the at least one opening comprises first and second openings lying in a plane, the at least one bore comprising third and fourth bores lying in the plane, the rib lying in the plane.
The rib thus guides the filament as it is being wrapped about the rotor into the sub-chambers out of the way of the rotor bores so that the filament free end can be later inserted into a rotor bore and locked to the rotor by rotation of the rotor. The rotor bores are not blocked when an end of the filament is initially wrapped about the rotor wherein the free end of the filament may later be attached to the rotor without interference from, the initial wrapped state of the filament.